1. Field of the Invention
The present invention relates to a recording apparatus capable of recording images on both sides of recording paper in an electrophotographic system, and more particularly, to a recording apparatus employing water-repellent recording paper such as an OHP sheet as a recording medium.
2. Description of the Related Art
There is conventionally a case that this kind of recording apparatus uses an OHP sheet as a recording medium on which an image is recorded. In the case where a conventional recording apparatus records an image on the OHP sheet, the apparatus performs specific feeding control because the OHP sheet is different from normal recording paper. That is, a feeding speed for the OHP sheet is made lower than that for the normal recording paper. It is because a thickness of the OHP sheet is greater than that of a sheet of the normal recording paper, so that it is necessary to fix the image with a higher temperature in the OHP sheet than in the normal sheet to improve fixing characteristics when the image is fixed. The feeding speed for the OHP sheet is thus decreased, whereby the fixing temperature for the OHP sheet is relatively increased to improve the fixing characteristics.
However, the aforementioned conventional recording apparatus has following problems when a color image is recorded on the OHP sheet.
That is, in order to prevent deterioration of an image quality, a recording apparatus with a function for recording color images cleans residual toners on a fixing roller, while coating an oil on a surface of the fixing roller to improve residual toner removing characteristics at the time of cleaning. It is because toners with a plurality of colors on the recording paper adhere to the fixing roller at the time of fixing, and leaving the adhering residual toners after the fixing results in that the residual toners adhere to next recording paper as mixed color stains. Thus, the color recording apparatus coats the oil on the fixing roller to improve the residual toner removing characteristics, and thereby prevents the image quality from deteriorating.
Meanwhile, since an OHP sheet is a recording medium made of a water-repellent material that does not absorb an oil, the OHP sheet tends to be discharged with an oil on a surface thereof after the fixing as compared to normal recording paper. Therefore, when images are recorded on both sides of recording paper and the OHP sheet is used as a recording medium, the OHP sheet has an oil on a surface thereof after an image on the first side thereof is fixed, and is returned to a paper path for the second-side recording with the oil thereon, whereby the oil adheres to a surface of a roller on the paper path, which causes the roller to be stained, and which further causes recording paper fed thereafter to slip.
The present invention is carried out in the view of the foregoing. It is an object of the present invention to provide a recording apparatus with a lo function of both-side recording capable of preventing a roller on a paper path from being stained and paper from slipping even when sheets of recording paper contain a water-repellent recording medium such as an OHP sheet.
In the present invention, when an instruction to perform the both-side recording for recording images on both sides of a recording medium is input, it is determined whether or not the recording medium on which an image is to be recorded is a water-repellent sheet that repels water. When it is determined that the recording medium is the water-repellent sheet, the water-repellent sheet is compulsively discharged, or set to wait at a position, before an image is transferred, enabling the sheet to be removed, thereby preventing the water-repellent paper with an oil on a surface thereof from being returned to a paper path for the second-side recording.
A first aspect of the present invention is a recording apparatus provided with an input section for use in inputting an instruction to perform both-side recording for recording an image on each of both sides of a recording medium, a determining section that determines whether the recording medium is a water-repellent sheet that repels water, and a controller that compulsively discharges the water repellent sheet when the both-side recording is instructed and the determining section determines that the recording medium to be subjected to image recording is the water-repellent sheet.
Thus in the case where the recording medium is determined to be the water-repellent sheet, although the both-side recording is instructed, compulsively discharging the water repellent sheet makes it possible to prevent the water-repellent sheet with an oil on a surface thereof from being fed again to a paper path, whereby the oil on the water-repellent sheet does not adhere to a surface of each roller arranged on the paper path. As a result it is possible to prevent the roller from being stained and to prevent next recording paper from being stained due to the stain of the roller, and further possible to prevent the next recording paper from slipping on the paper path due to the oil adhering to the surface of the roller.
Since usually different images are not recorded on both sides of a water-repellent sheet as a recording medium, the aforementioned aspect is not against a purpose of an operator, and is rather convenience. It is possible to prevent the occurrences of inconveniences in the apparatus due to the operator instructing the both-side recording on the water-repellent sheet incorrectly in the cases such that the operator instructs the both-side recording while misunderstanding that normal recording paper is stored in a paper cassette despite water-repellent sheets being stored therein, and that the water-repellent sheet is accidentally mixed among normal recording paper stored in a paper cassette.
According to a second aspect of the present invention, in the recording apparatus of the first aspect, when the both-side recording is instructed and further the determining section determines that the recording medium to be subjected to the recording is the water-repellent sheet, the controller compulsively discharges the water-repellent sheet after recording the image on one side of the sheet.
Therefore in the case where the recording medium is determined to be the water-repellent sheet, although the both-side recording is instructed, the water-repellent sheet is compulsively discharged after an image is recorded on only one side of the sheet. Hence, even if an operator instructs the both-side recording incorrectly while recognizing that the recording medium is the water-repellent sheet, the operator does not need to instruct the recording again. Therefore it is possible to prevent wasteful consumption of the water-repellent sheet that is not reusable from being caused by discharging the water-repellent sheet with only oil coated thereon without any image recorded thereon.
A third aspect of the present invention is a recording apparatus provided with an input section for use in inputting an instruction to perform both-side recording for recording images on both sides of a recording medium, a feeding mechanism that circulates a plurality of recording media on a paper path to pass through a fixing section in a predetermined order in the case of the both-side recording, a determining section that determines whether the recording medium is a water-repellent sheet that repels water, and a controller that compulsively discharges the water-repellent sheet and all the recording media present on the paper path when the both-side recording is instructed and further the determining section determines that the recording medium to be subjected to the recording is the water-repellent sheet.
Thus in the case of the feeding mechanism that circulates a plurality of recording media on a paper path in the both-side recording, when the recording medium is determined to be the water-repellent sheet, although the both-side recording is instructed, not only the water-repellent sheet but also all the recording media present on the paper path are compulsively discharged, whereby an area on the paper path is once emptied to start the recording operation from the first step, and therefore it is possible to prevent unnecessary recording media from being generated due to the recording order being disordered.
A fourth aspect of the present invention is a recording apparatus provided with an input section for use in inputting an instruction to perform both-side recording for recording images on both sides of a recording medium, a determining section that determines whether the recording medium is a water-repellent sheet that repels water, and a controller that sets the water repellent sheet to wait at a predetermined position before the image is transferred when the both-side recording is instructed and the determining section determines that the recording medium to be subjected to the recording is the water-repellent sheet.
According to a fifth aspect of the present invention, in the recording apparatus of the fourth aspect, the predetermined position where the water-repellent sheet is set to wait is a position corresponding to a cover for paper jam removing.
Therefore in the case where the recording medium is determined to be the water-repellent sheet, although the both-side recording is instructed, the image recording is not performed on the water-repellent sheet, which is set to wait at the predetermined position, before another position where the image is transferred, corresponding to the cover for paper jam removing, whereby it is possible to prevent the water-repellent sheet with an oil on a surface thereof from being fed again to a paper path. It is thereby possible to prevent the oil on the water-repellent sheet from adhering to a surface of each roller arranged on the paper path to stain the roller, and further possible to prevent next recording paper from slipping due to the oil adhering to the surface of the roller. Furthermore, since the water-repellent sheet with the oil only coated thereon without any image recorded thereon is not discharged, it is possible to prevent the water-repellent sheet that is not reusable from being used wastefully.
A sixth aspect of the present invention is a recording apparatus provided with a recording section that superimposes color images on an intermediate transfer material to transfer to a recording medium, an input section for use in inputting an instruction to perform both-side recording for recording images on both sides of the recording medium, a determining section that determines whether the recording medium is a water-repellent sheet that repels water, and a controller that sets the water-repellent sheet to wait at a predetermined position before the image is transferred when the both-side recording is instructed and the determining section determines that the recording medium to be subjected to the recording is the water-repellent sheet, where the color image is still stored on the intermediate transfer material after the water repellent sheet is removed, and the color image is transferred to another recording medium that is next provided.
The color image is thereby stored on the intermediate transfer material even when the water-repellent sheet is used incorrectly as a recording medium, whereby it is possible to transfer the color image to a recording medium fed next without forming again the same color image on the intermediate transfer material. As a result, it is possible to perform the reprinting speedy and efficiently after the water-repellent sheet is removed.
A seventh aspect of the present invention is a recording apparatus provided with a recording section that superimposes color images on an intermediate transfer material to transfer to a recording medium, an input section for use in inputting an instruction to perform both-side recording for recording images on both sides of the recording medium, a feeding mechanism that circulates a plurality of recording media on a paper path to pass through a fixing section in a predetermined order in the case of the both-side recording, a determining section that determines whether the recording medium is a water-repellent sheet that repels water, and a controller that sets the water-repellent sheet to wait at a predetermined position before the image is transferred when the both-side recording is instructed and the determining section determines that the recording medium to be subjected to the recording is the water-repellent sheet, still stores the color image on the intermediate transfer material after the water-repellent sheet is removed, and transfers the color image to another recording medium that is next provided, where the color image stored on the intermediate transfer material is deleted after the other recording media present on the paper path are removed after the water-repellent sheet is removed.
Thus in the case of circulating a plurality of recording media on a paper path in the both-side recording, when the water-repellent sheet is detected on the paper path, although the both-side recording is instructed, the recording operation is once stopped to remove the water-repellent sheet, while the color image stored on the intermediate transfer material is deleted after the other recording media present on the paper path are removed, whereby the color image is formed again on the intermediate transfer material according to the order to restart printing under a condition that not only the water-repellent sheet, but also the recording medium with an image recorded on one-side thereof are removed from the paper path. As a result, it is possible to prevent images for one side and the other side for each page from being recorded on different recording media with the sides inverted and/or the order disordered, and to prevent recording media with unnecessary images recorded thereon from being wastefully consumed.
According to an eighth aspect of the present invention, in the recording apparatus of either of the first to third aspects, the controller continues to store data of the image to be recorded on the recording medium when the controller compulsively discharges recording media including the water-repellent sheet, while deleting data of the image recorded on the recording medium when the controller discharges the recording medium normally.
Thus, the image corresponding to the compulsive discharge is stored in performing the compulsive discharge, while the image corresponding to the normal discharge is deleted after the recording operation is finished in performing the normal discharge. Therefore in the case of performing the compulsive discharge, re-recording is started by setting again an appropriate recording medium and instructing the recording. It is thereby possible to prevent the occurrence of a labor for transferring again the image to be recorded due to the compulsive discharge being performed.
According to a ninth aspect of the present invention, in the recording apparatus of either of the first to eighth aspects, the determining section has a sensor which detects that the recording medium passes through a position on a paper path, and a transmission sensor that detects the recording medium which passes through the position.
The recording media is thereby automatically determined to be the water-repellent sheet without an operator not designating that the recording paper is the water-repellent sheet by manual operation, whereby even in the case where the operator instructs the both-side recording incorrectly despite the water-repellent sheet being set, it is possible to assuredly prevent a roller on the paper path from being stained and paper from slipping.
A tenth aspect of the present invention is a recording method comprising the steps of detecting that an instruction to perform both-side recording for recording images on both sides of a recording medium is input, determining or not whether the recording medium on which an image is to be recorded is a water-repellent sheet that repels water, and compulsively discharging the water-repellent sheet when the instruction for the both-side recording is input and the recording medium to be subjected to the recording is determined to be the water-repellent sheet.
An eleventh aspect of the present invention is a recording method comprising the steps of detecting that an instruction to perform both-side recording for recording images on both sides of a recording medium is input, determining whether or not the recording medium on which an image is to be recorded is a water-repellent sheet that repels water, and setting the water-repellent sheet to wait at a predetermined position before the image is transferred when the instruction for the both-side recording is input and the recording medium to be subjected to the recording is the water-repellent sheet.